1. Field of the Invention
The present invention relates generally to apparatus used to eliminate fuel vapors commonly emitted from fuel tanks and fuel dispensing nozzles during the refueling process. Specifically, the present apparatus disclosed herein is a valve which may be adapted to fuel dispensing nozzles either formed as an integral part thereof or threaded therein which will allow the user to easily dispense fuel and syphon off the vapors which are emitted during that process.
2. Description of the Relevant Art
The relevant art includes U.S. Pat. No. 3,133,566, issued in 1964 to Hoss entitled: "Fueling Device", which discloses fueling device for feeding liquid fuel from a gas pump to a fuel tank vehicle including, a gas pump, a filling hose extending from and connected with the gas pump, a first coupling element having a first spring biased valve therein and being secured to the free end of said filling hose, a nozzle having a second coupling element and including means for opening said first spring biased valve, the first coupling element being connectable with the second coupling element simultaneously opening the first spring biased valve for a free flow of the fuel from the filling hose to the nozzle, a fuel tank adapted to be mounted in a vehicle, a filling line extending from and being secured to the fuel tank, a third coupling element having a second spring biased valve therein and secured to the free end of the filling line, and an intermediate fourth coupling element having means for opening said second spring biased valve opposite said second spring biased valve and being opened at its opposite ends, the first coupling element being connected selectively directly with the third coupling element to provide a direct connection between the first and third coupling elements and indirectly with the third coupling element by means of an intermediate connection of the first coupling element with the second coupling element and of the third coupling element with the fourth coupling element, providing an indirect connection of the first coupling element with the third coupling element, and the first valve and the second valve being opened simultaneously and the nozzle being received in the open end of the fourth coupling element during the indirect connection between the first and third coupling elements; U.S. Pat. No. 4,223,706 issued in 1980 to McGahey entitled "Closed Fuel System With Vacuum Assist", which includes a tight seal at the vehicle-nozzle interface for those vehicles which permit it, a vacuum assist device adapted to aid in collecting vapors from those vehicles the tanks of which cannot be sealably engaged, and the use of a positive displacement reciprocatory hydraulic motor which is driven by the dispensed gasoline flow, the motor thus actuates this reciprocatory vapor pump, thereby controlling the volume of vapor pumped in relation to the volume of gasoline dispensed; U.S. Pat. No. 4,354,536 issued in 1982 to Moss, entitled "Gasoline Dispensing Nozzle" discloses a nozzle having a valve housing and an elongated tube extending therefrom, the nozzle is provided with at least a slot near its open end, a latch is mounted within the nozzle which is movable between a first position, extending outwardly of the slot and a second position inwardly within the nozzle, the latch may be spring biased or normally controlled to extend outwardly, so that once inserted within the vehicle, the gas tank will lockingly engage under its lip, the latch is provided with structure operable from the exterior of the nozzle which can selectively retrack the latch and release the nozzle from the gas tank; U.S. Pat. No. 4,429,725 issued in 1984 to Walker, entitled "Dispensing Nozzle for Vacuum Assist Vapor Recovery System", discloses an automatic shut-off nozzle adapted to be utilized in a vacuum assist type vapor recovery system, including, a nozzle body having an inlet and an outlet for liquid to be dispensed, a filling spout attached to the nozzle body adapted for loose fitting reception in a vehicle tank fill pipe and having an internal conduit for liquid connecting to the body outlet and an external conduit for vapor return surrounding the liquid conduit, the two conduits defining an annular passage for conducting vapor from the vehicle tank to a vapor return conduit means in the nozzle body, a valve in the body for controlling the flow of liquid through the body from the inlet to the outlet, a manually operated means for controlling the operation of the valve and, vacuum responsive release means to allow closing of the valve and stoppage of liquid flow when a predetermined partial vacuum is induced within the nozzle, venturi means responsive to liquid flow through the body for including a partial vacuum and an interconnecting passage between the vapor return conduit means to the venturi means normally allowing the flow of vapor from the vapor return conduit means to the venturi means to limit the partial vacuum induced, thereby, and the interconnecting passage being located at a point in the vapor return conduit which becomes full of liquid at such times when liquid begins to be aspirated from the vehicle tank through the vapor return conduit, and a check valve within the nozzle body for closing the vapor return conduit valve which is actuated to the open position by liquid pressure within the nozzle body when the control valve and the nozzle body are open; and U.S. Pat. No. 4,827,987 issued in 1989 to Faeth, entitled, "Liquid Fuel Blockage Removal Device With A Venturi and bypass Passages", discloses a device for mounting in a fuel dispensing hose that has a flexible inner tube defining the fuel conduit, and a tubular outer sleeve that defines with the inner tube an annular vapor return passage, and the device includes an aspirating block adapted for serial connection with inner tube within the outer sleeve, and the section comprises a cylindrical block that is connected in series with ends of the inner tube and defines a venturi or jet pump forming part of the fuel conduit, and the block also includes bypass passages for fuel to bypass the venturi and to increase the fuel flow through the block, and the aspirating block also has radial aspirator ports which communicate between the venturi throat or jet pump and the annular vapor return passage, and each radial aspirating port includes a check valve to permit only one way fuel flow from the fuel outlet to the vapor passage.
As can be seen the aforementioned prior art while related to the present apparatus disclosed herein either deals with the problem of controlling the fueling of a tank, the dispensing of fuel and only peripherally the related problem of controlling fuel vapors by passive means if at all. However, these generally fail to disclose a simple valve which is adaptable to the conventional fuel pump found at most fuel dispensing stations which allows the collection of vapors in an amount proportional to the fuel dispensed into a fuel tank and operable by the displacement by dispensed fuel without the necessary assist of vapor pumps or a hydraulic motor. Furthermore, the relevant art fails to disclose an apparatus which will keep fuel from flowing through the fuel nozzle unless the fuel vapors can be drawn for proper disposal, provide a channel for the evaporative vapors to travel through for disposal and prevent the loss or leakage of vacuum from any fuel nozzle that is not in use that would reduce the efficiency of those that are being used. It should be noted that the present apparatus disclosed herein accomplishes all the aforementioned objectives mentioned above.